Magnetoelectric magnetometers

Abstract

Key features of magnetoelectric (ME) sensors for measuring the magnetic field, electric current and microwave power are discussed. ME sensors are shown to have advantages over semiconductor ones in the sensitivity, low price and radiation resistance. To predict the feasibility of a composite for sensor application, we propose the nomograph method based on given parameters of the composite components. The sensor sensitivity depends on the construction and the materials parameters of the ME composite and bias magnetic field. ME laminates offer opportunities for low frequency (10−2–103 Hz) detection of low magnetic fields (10−12 Tesla or below) at room temperature in a passive mode of operation. Any other magnetic sensor does not reveal such combinations of characteristics. Current sensing based on ME effect is a good choice for many applications due to galvanic isolation between the current and measuring circuit. For increasing the sensor sensitivity one needs to use the ME composite based on materials with high magnetostriction and strong piezoelectric coupling. Microwave power sensors based on composite materials have a wide frequency range up to hundreds of gigahertz, stable to significant levels of radiation, and a temperature range from 0 K to the Curie temperature. In the microwave region, it is possible to use selective properties of ME materials, that enables one to create a frequency-selective power sensor with fine-tuning.